Radio frequency circuits



June 17, 1930. E. A. KUEN RADIOFREQUENCY C IRCUITS 2 Sheets-Sheet 1 Filed April 7, 1927 June 17, 1930. E. A. KUEN RADIOFREQUENCY CIRCUITS v 2 Sheets-Sheet 2 Filed April 7, 1927 f T I I will now'take up the description of Fig 1.

qInfthis embodiment theusua-l antenna cou ler 9 1s employed, with ,agljconnection' lO to grid oithe'tube ll. Following this tube is the radio "freqileny trans'former 12 which Q1 ejinbo diesvtwro vse'conclzny windingaf The 'priw j mary of this ftransformerfis con ne cted with thEPIaLte f the first 1iube, as a613, While one." V

(if the, transformerecbndaries is connected V or principal secondaries as to filament return in that instead'of a filament'return through a potentiometer there is direct connection ofeach principal secondary to the filament cirfilament" circuit in the same manner as are the principal secondaries.

secondary is employechtheconnections being in every respect identicalwith those shown in Fig. 3, as will be seen two circuits. 7 V

Andnow we come to the two grid tube adaptations of the invention, which are disclosed in Figs. 5, 6,7 and 8; In Figib theidentical circuit as is disclosed in Fig. 1 is shown. {The dead ended 1 additional secondaries of "the inspection of the transformers 29 and 30 are shown, but in all the tubes 31, 32 and 33' are found two grids.

In this two grid tubefarrangement there 7 is however separate connection made toeach of the grids. One offtheseconne'ctions ('34,v

35) is ifrom one' secondary of a preceding transformer forwardly to oneof the grids of a s'ucceeding'tube, while the other connection I (36', 37) isimade from 'the other secondary backwardlv through a blocking condenser as exemplified at. 38 and 139 respectively to the other of the gridsiineach tube; V

r In Fig. 6 I'have shown identically the same circuitas that shown in Fig. Qwith the exception that instead of the two secondary con nections being made to the onergrid, the two vgrid tube permits of one grid beingused for" each connect-ion.

1 Fig. 7 shows identically the same circuits e e QfFig-c -eX Pt as to heii b a grid tube. Here will be foundjthe separate grids used for the twoigrid connections which.v are providedfor eaeh -tube;

1511 doubt quite obvious to thoseskilled in capacity;

I In Fig.8 will be found. the identical circuit 7 V -which Ihavefshown inFig. 4 except thata r 7 two grid'tuhe has'been adapted thereto: V

'7 Thefunctioning of'the c'ircuitl have shown r a stepping of the energy impulses impressed upon the two grids out of phase just enough to bring about a surprising clearness of tone and volume with a minimized noise and static level. -This I also find to be accomplished with increased sensitivity and: correspondingly increased selectivity and ease oftuning; In Fig. 4 I haveshown diagrammatically a portion of a circuit in which a centertapped cla mo sr V 1. In a radio frequency amplification cir- "Having thus described my invention what .cuit, the combination of aseries of alternately associated electron e1n1ss1on devices and radio 3 frequency transformers, said transformers.

having i duplicate secondary windings connectecl with duplicate grids in all the devices,

the connection of. one ofj'said secondaryfwindingsf with one ofthe 'gridsbeingefi'ec'ted througha condenser in series, therewith,the

want," u a ,r r c. 2. In a radiojfrequencyamplification circuit,the combination of a series offalternatel'y associated elr'actron emission devices and radio frequency, transformers, said transformers having duplicate secondary windings con- 'nected. with duplicate grids in all thedeviees, the connection of one of said secondary windings with/one of the'grids being effected through a c ondenser'in' series therewith, the connectionbf the other" of said secondary windings with the other of the grids'being effected, with "acondenser, in parallel therewlth, one of said condensersbeing ofva riable ,Intefstimony whereof I have hereunto affi y. g t H 7V enteringinto the functioning ofthiscircuit,

HoweverI will point out that the subjection of all; the principal" secondaries t0: the. same input and other voltage conditions will cause;

V thenothe'r or-additional secondaries to respond; H I i V in the samemannerthrough inductive action, 1

7 However ether-action of the additional sec; ondaries willbe retarded slightlyf bya-block- V r ingflaotion of theicondensers interposedbe-j tween the-mend the grids to which these sec..- a ondaries are -indirectlyj;connected rThis zc-causes the amplified signalenergy ,to be smo'othed o'ut by allowingit'to be fed-gradu- I i i I ally'so'ihat thtpblectionable. shespf signal" ,1; .;j I 7i 

